Spermacoce latifolia Aubl.

West Indies (Guadeloupe) : Spermacoce latifolia flowers all year round.
Madagascar: Spermacoce latifolia germinates heavily at the beginning of the rainy season and fruits at the end of hot, rainy season.

Spermacoce latifolia is an annual or short-lived perennial species. It multiplies by seed.

It should be noted that in many weed science books, S. latifolia and S. alata are considered synonymous and are usually referred to as S. alata. This is particularly true for weed populations in the old world. These two species are now well considered as two distinct taxa, and clearly distinguishable morphologically and by their geographical distribution.
S. latifolia occurs in tropical Central and South America, and has been introduced into Florida, West Africa, Central Africa, Madagascar, India, Southeast Asia to Australia and some Pacific islands, whereas S. alata occurs only in the northern part of South America.

Ecologically S. latifolia is a sunny plant, often a weed of crops, while S. alata is a shade plant, never a weed.

The main morphological distinguishing criteria of these two species are : 

Spermacoce latifolia is a ruderal species and a weed of cultivated fields

West Indies: Spermacoce latifolia is a native species present only in Guadeloupe. It is a ruderal and weed species that prefers ferralitic clay soils and tolerates wet and temporarily flooded soils. It is present from 20 to 200 m in altitude.
French Guiana: Spermacoce latifolia is frequent at the edge of the canals of the rice polder of Mana, and is a weed of crops and pastures in sunny situations. It has only been observed north of Cayenne in the regions of Saint Laurent du Maroni, Mana and Sinnamary.
Madagascar: The species grows on relatively rich soils: ferralitic soils with varying degrees of humus in sunny or lightly shaded areas. It is a weed of rainfed crops (rainfed rice, maize and cassava based cropping systems, more or less extensive), in fallows and pastures in humid (eastern slopes) and sub-humid areas up to 1000 m altitude (Middle West, Middle East, North West).
Mauritius: Absent.
Reunion: Absent.

Global harmfulness

Spermacoce latifolia is a dominant weed in agricultural fields.

Local harmfulness

Benin: Rare and not abundant.
Burkina Faso: Rare and not abundant.
Cote d'Ivoire: Frequent but not abundant.
French Guiana: This species is infrequent and not very abundant in vegetable or fruit crops, as well as in pastures.
Madagascar: Spermacoce latifolia is a species recently introduced in Madagascar; it is an invasive weed, common and abundant in the Middle West, the Middle East and the East Coast. It is particularly aggressive in humid areas at low altitude (East Coast), which became abundant and dominant. It is rapidly expanding in sub-humid zone, up to 1000 m altitude. S. latifolia is particularly harmful in cropping systems based on rainfed rice and corn on the East Coast.
Mauritius: Absent.
Reunion: Absent.
West Indies: Spermacoce latifolia is a common weed in crops and not very damaging in Guadeloupe. Tolerant to some herbicides, it can become locally abundant in chemically weeded fruit crops.

Global control

Cultural control: Hoeing and hand weeding at 14 and 28 days after rice emergence are effective in controlling and preventing upland rice crop loss.
Chemical control: MCPA at 0.4 kg ha-1 applied 25-30 d after emergence gives good control.

For global information on weed management in irrigated and low-land rice in Africa, click here.

For directions for management of annual broad-leaved weeds in irrigated and low-land rice in Africa, click here.


Local control

Madagascar: The manual weeding of Spermacoce latifolia remains the main means of control used but inefficient and costly.
West Indies (Guadeloupe): Manual and mechanical weeding techniques are sufficient to control the growth of Spermacoce latifolia.

Herbarium pictures Recolnat : https://explore.recolnat.org/search/botanique/simplequery=spermacoce%2520latifolia